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M. o. "scHuR Oct. 18, 1932.

SELF ADJUSTING VALVE Filed April 12. 1930 2 Sheets-Sheet l Oct. 18, 1932. M, Q SCHUR 1,882,990

SELF ADJUSTING VALVE Filed April 12, 1930 2 Sheets-Sheet 2 j? Z W N 7% i I 772057fi7 Patented Oct. 18, 1932 UNITED STATES PATENT o MILTON O. SCHUR, F BERLIN, NEW HAMPSHIRE, ASSIGNOR TO BROWN COM PANYQ OI BERLIN, NEW HAMPSHIRE, A CORPORATION OF g SELF-ADJ USTIN G VALVE Application filed April 12;

' than that desired so that diluting fluid may be added thereto in varying quantities to offset the variation in viscosity of the incoming stream and to dellver the stream wlth a substantially constant viscosity by reason of regulated dilution of the incoming stream. To this end an automatic valve may be employed which is regulated in response to a feeling mechanism placed in the stream at the point of delivery. Such mechanism may be sensitive to variations in viscosity from the desired standard (or from any other standard characteristic desired), the valve being operable by the feeling mechanism to open or close so as to regulate the rate of supply of diluting fluid and thus to maintain the consistency of the viscosity of the delivered fluid substantially constant. A practical use of such apparatus is found in pulp mills wherein streams of pulp stock are supplied from a beater or elsewhere and must be diluted to a substantially uniform consistency o'r viscosity before being delivered to a paper making machine or other mechanism for operating on the pulp. The consistency of the pulp stock coming from a beater is subject to occasional fluctuation of considerable magnitude owing to usual conditions of manufacture. Thus it is imperative to provide a responsive mechanism for regulating the rate of supply of diluting water so as to deliver the pulp stream with a substantially uniform consistency. If the pulp is supplied in a stream of relatively constant magnitude, the capacity of the valve through which the diluting water is admitted can be calculated accordingly, a valve of small maximum capacity being desirable for 1930. 'serialfiNo. 443,675.

"a reiatiVdy ll pulp stream, while a valve of large maximum capacity is desirable for a large pulp stream. Since the requirements of rate'of supply of pulp stock are liable to vary widely from time to time so that vthe ii stream of pulp is at times relatively small and at times relatively large, it has heretofore been diflicul't to operate the automatic valve satisfactorily for diluting such a variable stream. If, for example, a valve of large} capacity is provided for a large stream, such a valve is unsuitable when the stream passing through the apparatus" is small, since asmall variation from standard consistency in the delivery point of the stream results in a-= change of the opening of the large capacity valve which results in a relatively large alteration in the rate of supply of diluting water to the small stream of stock to be diluted. Hence the consistency of the delivered' stock tends to fluctuate back and forth asthe supply of diluting'water is changed too rapidly. On the other hand, if a valve hastoosmall a capacity for the stream, it may at times be unable to supply diluting water at a suflicient rate, even when wide open.

According to the present invention, this difliculty is overcome by providing a Valve of variable capacity together with mechanism by which this capacity is automatically altered as the valve reaches either limiting position of normal operation. Thus if the Valve is operated at large capacity for a large stream of pulp, and if the stream is consid erably diminished so as to require a valve of small capacity, operative action of the valve automatically changes the capacity of the valve to suit'the requirements of the stream.

For a more complete understanding of the invention, reference may be had to the description of an embodiment thereof which follows, and to the drawings, of which,

Figure 1 represents a longitudinal sectional view of an embodiment of the invention.

Figure 2 is a section on the line 2'2 of Figure 1. l

Figure 3 is a'section on the line- 33 of Figure 1.

Figure 4 is a section on the line 44 of Figure 1.

Figure 5 is a plan view of a portion of the apparatus showing the arrangement of cam "members for adjusting the capacity of the valve.

Referring to the drawings in detail, the valve through which the stream of diluting liquid may be controlled comprises a tubular casing in which is slidably fitted a tubular valve member 11. The casing 10 is provided with a lateral opening 12 which leads into a chamber 13 connected to an intake pipe 1 L In the embodiment of the invention illus trated in the drawing, an outlet 15 is provided in the housing 10. The tubular valve member 11 is likewise provided with a lateral opening 16 capable of registry with the opening 12. When the openings 12 and 16 are in registry the diluting liquid is thus provided with a path through the inlet pipe 14, the chamber 13, the openings 12 and 16 and out through the port 15 to a suitable pipe (not shown). provdied with a suitable stem 20 which extends outwardly from an end of the housing 10, a stufiing box 21 being provided to prevent leakage. The valve member 11 is movable axially and angularly by actuation of the stem 20 so as to vary the area of registry of the openings 12 and 16. Axial movement of the valve member 11 results in a variation of the length of the area of registry, while angular movement of the valve member results in a variation of the width of the area of registry. The valve stem 20 may be conveniently attached to mechanism (not shown) which is, in turn, responsive to the desired characteristic of the delivered liquid. Such mechanism, which per se forms no part of this invention, may be adapted to move the stem 20 in a direction to close the valve in response to a viscosity of the liquid lower than standard and to move the valve toward its open position in response to a greater than standard viscosity in the delivered liquid. Thus the operating stroke of the valve memher is, in this case, its axial travel.

In order to vary the capacity of the valve, the valve member may be angularly adjusted so as to widen or narrow the area of registry between the openings 12 and 16. According to the present invention mechanism is provided for automatically regulating the capacity of the valve. This mechanism may comprise an arm 25 secured to the stem 20 and projecting radially therefrom. The outer end portion of this arm moves in a direction parallel to the axisrof the valve member 11 as this member is operatively reciprocated. A pair of cam members 26, 27 may be mounted in the field of motion of the outer end of the arm 25, these cams, as shown in Figure 5, having sloping faces 28 and 29 respectively against which the outer end of the arm 25 is The tubular valve member 11 is adapted to engage as the valve member 11 approaches one or the other limit of its axial movement. As illustrated on the drawings, the closing movement of the valve member 11 is toward the left. When approaching the end of such movement, the arm 25 comes in contact with the cam surface 28 so that further closing movement of the valve member 11 results in a rotation of this valve member in a direction to narrow the area of registry between the openings 12 and 16, and thus to diminish the capacity of the valve. Thus the action of the cam surface 28 on the arm 25 is in a directionto augment the effect of the motion of the valve member 11, that is, in this instance, to diminish the area of registry between the openings 12 and 16. When the valve has thus been sufliciently closed to reduce the supply of diluting liquid to the desired amount, the valve may then be at rest until the incoming supply of stock thickens, requiring a larger supply of diluting liquid. This results in an axial movement of the valve member 11 in a direction to open the valve without altering the diminished capacity of the valve since this axial movement moves the arm 25 away from contact with the cam surface 28 so that there is no further rotation of the valve member 11 unless and until the arm subsequently moves into contact again with the cam surface 28 or with the cam surface 29, whereupon the capacity of the valve may again be altered. If the closing of the valve has resulted in part from diminution in the stream of stock passing through the apparatus, the reduction of the capacity of the valve improves the action of the valve in controlling the dilution of the diminished stock stream.

If, now, the stream of stock increases so that a larger flow is required to compensate for the variations in the viscosity of the in coming stock, the valve will adjust itself as follows. The increase in the stream of stock will call for an increase in the quantity of diluting water supplied thereto, so that the valve member 11 and the arm 25 will move toward the right. Since at this time the capacity of the valve is relatively small, by reason of the narrowness of the area of registry between the openings 12 and 16, this movement of the valve member 11 toward its open position will at first be insufficient to meet the requirements of the larger stream of stock. lVhen, however, the valve member approaches its fully open position, the outer end of the arm 25 travels into operative contact with the cam surface 29 so that further movement of the valve member toward the right results in a widening of the area of registry between the openings 12 and 16 and thus rapidly increases the capacity of the valve to a point where it is capable of responding sufliciently for the needs of the enlarged stream of stock passing through the apparatus. At this time further opening of the valve ceases, and the width of the area of registry and hence the capacity of the valve remains constant until the arm is again brought into operative contact with either of the cam surfaces 28 or 29.

I claim:

1. A self-adjusting valve comprising a casing having a port therein for the flow of fluid through the valve, a valve member movable to close said port, said valve member having a cut-away portion movable in two directions into and out of registry with said port to open and close a passage through the valve, one of said directions of motion being for operating movement and the other direction of motion for adjustment of valve capacity, and means actuable by approach of said valve member to either end of its operating stroke to impart movement to said valve member in its adjusting direction to augment the effect of the motion in said operating direction.

2. A self-adjusting valve comprising a tubular housing having a valve opening through a side thereof, a tubular valve member slidably fitted within said housing for I reciprocation and rotation therein, said member having a lateral opening adapted to register with the opening in the housing, a valve stem actuable to impart axial operating movement and angular adjusting movement to said member, and means actuable by the approach of said member toward either limit of its operating stroke to impart angular adjusting movement thereto.

3. A self-adjusting valve comprising a tubular housing and a. tubular valve member slidably fitted therein for axial and angular movement, said housing and member each havin an opening in the side wall thereof and being movable to bring said openings into registry, a stem on said member actuable to impart movement to said member, and means for angularly adjusting said member upon its approach toward either end of its stroke, said adjusting means including an arm extending radially from said stem and a pair of cam elements engageable by the outer end portion of said arm as said stem approaches the limits of its stroke.

4. A self-adjusting valve comprising a tubular housing, a tubular valve member slidably fitted for axial and angular movement therein, said housing and member having rectangular apertures therein movable into registry, a stem secured to said member and actuable to move said member axially to vary the length of the area of registry of said openings, said stem also being actuable to rotate said member to vary the width of area of registry of said openings, and means for adjusting the width of the area of registry by the approach of said member to either limit of its axial throw, said means including an arm extending radially from said stem, a diagonal cam surface in the path of the end portion of said arm and engageable by said arm when said member approaches its position for maximum length of registry of said openings, said cam being arranged to cause 1 adjusting rotation of said member to increase the width of the rigistry of said openings, and a second cam engageable by said arm near the opposite end of the stroke of said member, said second cam being arranged to rotate said member by engagement with said arm to decrease the width of registry of said openings.

5. A self-adjustin valve comprising a valve having a port therein, for the flow of for adjustment of the capacity of the valve,

and means acting automatically upon the approach of said member toward either limit of its operating stroke to impart to said valve member movement in the direction for adjusting the capacity of the valve.

6. A self-adjustingvalve comprising a casing having an opening therein, a movable valve member having an aperture adapted to register with the opening in said casing to permit the flow of fluids through said valve, means for moving said member longitudinally of said opening to vary the length of the area of registry of said opening and aperture, and means operable by longitudinal movement of said member near both extremities of its stroke for adjustably altering the width of said area of registry.

7 In apparatus of the class described, a stem longitudinally reciprocable through a definite stroke and rotatably adjustable through a limited angle, and means actuable by longitudinal motion of said stem through the extreme portions only of its stroke for rotatably adjusting said stem.

In testimony whereof I have aflixed my sig 7 nature.

MILTON O. SCHUR. 

